(19)

(11)

EP 4 241 417 A1

(12)

(43) Date of publication: 13.09.2023 Bulletin 2023/37 (21) Application number: 21890125.4 (22) Date of filing: 05.11.2021

(51) International Patent Classification (IPC):  H04L 9/08(2006.01) (52) Cooperative Patent Classification (CPC): H04L 9/50; H04L 9/3239; H04L 9/085 (86) International application number: PCT/US2021/058199 (87) International publication number: WO 2022/098964 (12.05.2022 Gazette 2022/19)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME Designated Validation States: KH MA MD TN (30) Priority: 05.11.2020 US 202017090363 (71) Applicant: Polysign, Inc. Oakland, CA 94612 (US)

(72) Inventors: BRITTO, Arthur Oakland, CA 94612 (US) SCHWARTZ, David Oakland, CA 94612 (US) BRUNSON, Zack Oakland, CA 94612 (US) STILLE, Lukas Oakland, CA 94612 (US) VELAGAPALLI, Arun Oakland, CA 94612 (US) MAHENDRU, Nitin Oakland, CA 94612 (US) PAPAHADJOPOULOS, Kimon Oakland, CA 94612 (US) (74) Representative: Boult Wade Tennant LLP  Salisbury Square House 8 Salisbury Square London EC4Y 8AP London EC4Y 8AP (GB)